The advent and prevalence of e.g. portable audio devices has led to the widespread use of earphones for providing audio to users. Due to the proximity of the earphone to the ear, it is possible to generate high sound pressure levels. As this can furthermore be achieved without inconveniencing other people, it has led to a user behavior that often results in dangerously high sound pressure levels being applied resulting in a high risk of hearing damage. For example, the widespread use of in-ear earphones has resulted in many users often listening to audio at excessive levels.
The risk of hearing damage due to listening to e.g. portable audio players using earphones is of growing concern. For example, regulatory restrictions on the maximum volume levels that can be provided by portable devices are being discussed or implemented in many jurisdictions. However, such fixed restrictions tend to be inflexible and provide unsatisfactory protection as they may not be suitable for the specific scenario in which the portable audio player is used.
Indeed, the risk of hearing damage in particular arises due to the high playback levels that are possible with portable audio players and to the frequent use of such audio players in conditions that may have a high level of background noise. Indeed, the use of portable audio devices has resulted in headphones being used in more diverse environments and increasingly often being used in environments with a high level of ambient sounds or noise. This results in the difficult trade-off between a volume level that is sufficiently high to make the desired audio dominant and the desire to keep the volume level sufficiently low to avoid hearing damage. Users in a noisy environment will tend to increase the volume to levels that may have damaging effects if sustained for longer periods. Therefore, there is a desire for allowing the volume level and thus the produced sound pressure levels to be automatically controlled to provide a better trade off than typically selected by users. Accordingly, there is a desire to provide a better control of the volume of audio presentation such as e.g. from portable audio players. In particular, it may be desired to implement automatic volume controls that restrict the generated sound levels to a level that is unlikely to cause hearing damage.
US20070129828A1 discloses a system wherein a portable audio player may automatically adapt the volume such that the risk of hearing damage may be reduced. The approach is based on a restriction of the accumulated sound dosage from the audio player such that this does not exceed values that are considered to cause hearing damage. This is accomplished by defining the maximum allowed volume setting on the portable device based on the exposure time and the quiet time in between which allows the ear to recover from the sound exposure.
However, the approach may not be optimal in all scenarios. For example, a disadvantage of any system that estimates the potential for hearing loss based only on the usage of the audio player is that it does not reflect or take into account other sounds that the user may be exposed to. For example, it cannot be ensured that a quiet time in which the audio player is not used is indeed quiet and that the user is not exposed to a possibly high sound level. Therefore, it cannot be guaranteed that the ear is able to recover during the time in-between two sessions of listening to the audio player and therefore the risk of hearing damage remains.
Hence, an improved control of volume levels would be advantageous and in particular a system allowing increased flexibility, increased adaptability, reduced complexity, increased hearing protection and/or improved performance would be advantageous.